Before the driver applies the brakes ( with the reaction time ):
d 1 = v0 · t = 20 m/s · 0.53 s = 10.6 m
After that:
v = v0 - a · t1
0 = 20 m/s - 7 · t1
7 · t1 = 20
t1 = 2.86 s
d 2 = v 0 · t1 - a · t1² / 2
d 2 = 20 m/s · 2.86 s - 7 m/s² · (2.86 s)²/2 = 57.2 m - 28.6 m = 28.6 m
d = d 1 + d 2 = 10.6 m + 28.6 m = 39.2 m
Answer: the stopping distance of a car is 39.2 m.
(x-2)(x+7)=0
Equate each bracket to zero;
x-2=0
x=2
x+7=0
x=-7
x=2, x= -7
Answer:
0.86°
Step-by-step explanation:
The relations between trig functions and sides of a right triangle are summarized in the mnemonic SOH CAH TOA. It tells you the relation between an angle and its adjacent and opposite sides is ...
Tan = Opposite/Adjacent
__
<h3>angle from the bat</h3>
The geometry described in the problem statement is modeled by the right triangle shown in the attachment. (The horizontal scale has been compressed.) The angle of interest has an adjacent side of 400 ft. Its opposite side is the additional elevation the ball must have to clear the fence (8 ft - 2 ft) = 6 ft.
For angle α, we have the relation ...
tan(α) = (6 ft)/(400 ft) = 0.015
The inverse tangent function can be used to find the angle from its tangent:
α = arctan(0.015) ≈ 0.859372°
The angle of elevation needs to be a minimum of 0.86°.
Answer:
it will be more wildfires longer periods of droughts
Length (L): 2w + 6
width (w): w
Perimeter (P) = 2L + 2w
228 = 2(2w + 6) + 2(w)
228 = 4w + 12 + 2w
228 = 6w + 12
216 = 6w
36 = w
Length (L): 2w + 6 = 2(36) + 6 = 72 + 6 = 78
Answer: width=36 ft, length = 78 ft